Apparatus for sinking casings in the construction of caissons



Sept. 16, 1969 A. R. JOHNSON 3,467,203

APPARATUS FOR SINKING CASINGS IN THE CONSTRUCTION OF CAISSONS Filed June29, 1967 4 Sheets-Sheet 1 \v JZ JO 1 3 3 33 1| 4 ,1//Q4// l V/ %f F. 2 EINVENTOR.

M W h M EORNEYS Sept. 16, 969 A. R. JOHNSON 3,457,203

APPARATUS FOR SINKING CASINGS IN THE CONSTRUCTION OF CAISSONS Filed June29, 1967 4 Sheets-Sheet 2 l N VENTUR.

4 Sheets-$heet 5 A. R. JOHNSON CONSTRUCTION OF CAISSONS APPARATUS FORSINKING CASINGS IN THE Q Q Q m Sept. 16, 1969 Filed June 29, 1967INVENTOR. A 4F K oy/v.5

VWf'hRA/EYS Sept. 16, 1969 Filed June 29, 1967 A. R. JOHNSON 3,467,203APPARATUS FOR SINKING CASINGS IN THE CONSTRUCTION OF CAISSONS 4Sheets-Sheet 4.

(99 92 I: INVENTOR. 9/// J 44; Joy/V50 94 4434 W, @MATTORNEYS UnitedStates Patent 3,467,203 APPARATUS FOR SINKING CASINGS IN THECONSTRUCTION OF CAISSONS Alf R. Johnson, 7660 Marmora Ave., Skokie, Ill.60076 Filed June 29, 1967, Ser. No. 649,992 Int. Cl. E21c /10, 1/06;E02d 5/34 US. Cl. 173-159 28 Claims ABSTRACT OF THE DISCLOSURE A rig forboring and sinking casings in the construction of caissons including anexpansible-contractible collar for frictionally gripping a casing forjoint movement therewith and guided on a rig frame for vertical androtational movement only. Horizontally extending hydraulic rams aremounted on the collar for expanding and contracting the same and otherhorizontal rams arranged to move vertically with the collar on the framefor rotationally oscillating the collar relative to the frame. Thecollar is interposed between a pair of spaced interconnected horizontalcollar plates guided for vertical movement only on spaced vertical slideguides mounted on the frame. Bearings are interposed between the collarand the collar plates for relative rotation therebetween and verticalhydraulic rams interconnect the frame and the collar plates for movingthe collar plates and the collar vertically.

Background of the invention This invention relates generally to caissonconstruction apparatus and more particularly to apparatus for boring andsinking casings.

In the construction of caissons for foundations and the like a hole isformed in the ground and a large metal tube or casing is disposed in thehole. The casing is then gradually filled with concrete and is raisedslowly at a rate which corresponds to the rate at which the concretebegins to set.

It is preferable to form the hole in which the casing is disposed byboring the casing itself into the ground and then removing the dirt fromwithin the casing, rather than by auger-drilling the hole and thensubsequently dropping the casing into the hole. One important reason forthis preference is that an auger-drilled hole must be oversized withrespect to the outside diameter of the casing, thus leaving a gapbetween the casing and the wall of the hole after the casting is inplace within the hole. Because of this gap the dirt surrounding thecasing may separate from the wall of the hole and fall into thestill-wet concrete in greater or lesser amounts depending upon theconditions of the soil. If this occurs the caisson may be defective andsubstantial losses may be incurred.

A preferable manner of forming the hole is to bore the casing itselfinto the ground and progressively remove the dirt from within the casingas the casing sinks further into the ground. A lower or leading edge ofthe casing is provided with cutting teeth and the casing is rotationallyoscillated while a downward force is simultaneously applied thereto. Thelower edge of the casing always leads the removal of dirt from withinthe casing until the casing is bored to its final depth.

This preferred method almost completely eliminates the likelihood ofdefective caissons due to back-fill of dirt into the wet concretebecause of the elimination of the gap between the casing and the wall ofthe hole and hence the elimination of the space through which the dirtcan fall into the concrete. Even as the casing is being removed from thehole the thickness of the gap between the periphery of the concretecaisson itself and the wall of the hole is merely the thickness of thewall of the casing.

Ice

Apparatus for forming caissons in this preferred manner is known in theart. Such apparatus is not completely satisfactory, however, in terms ofboring speed, reliability, durability, accuracy in forming the hole,ability to satisfactorily accommodate out-of-round casings andmaintenance requirements.

Such known apparatus includes a radially expansible and contractiblecylindrical collar for receiving and clamping the casing. The collar isnot adapted to engage the casing completely around the peripherythereof, however, and instead usually maintains only point contact withthe casing. Such point contact may cause crimping of the casing due tothe high gripping pressures required to provide the necessary frictionalforces between the collar and the casing, and furthermore will notcorrect the shape of casings which may be out-of-round due to defects inmanufacture or through use.

The collar is suspended from a frame in a manner which enables it tomove horizontally as well as vertically, thus offering no guidance tothe casing. Furthermore the collar is rotationally oscillated by acomplicated mechanical linkage which must pivot in two directions aswell as extend and retract as the collar is oscillated. The deficienciesnoted above in known casing sinking are due primarily to this manner inwhich the collar is constructed and the manner in which it is mounted onthe frame and moved vertically and rotationally relative thereto.

Summary of the invention The casing sinking apparatus of the presentinvention may be briefly summarized as comprising a frame adapted to besupported in a horizontal casing-boring position, anexpansible-contractible casing gripping collar, means mounting thecollar on the frame for relative vertical and rotational movement only,means for selectively expanding and contracting the collar and means forselectively vertically and rotationally moving the collar relative tothe frame.

The collar comprises a plurality of overlapping interdigitated pivotallyinterconnected links arranged in a circular pattern for completelysurrounding the casing to provide frictional gripping engagementtherewith around the entire periphery of the casing. A master spacerlink maintains the circular configuration of the collar as the collar iscontracted so that the casing is gripped circumferentially continuouslytherearound and so that any outof-round of the casing is corrected.

The collar mounting means comprises a pair of horizontal collar platesdisposed at opposite axial ends of the collar and guided for verticalmovement only on a plurality of vertical slide guides connected in fixedassembly to the frame. Bearing means are interposed between the collarand the collar plates for relative rotational movement therebetween.

A plurality of reaction beams maintain the collar plates in spacedparallel relation and are fixedly secured thereto. The collar isoscillated about its axis of rotation by a plurality of hydraulic ramswhich interconnect the collar and the reaction beams and thus arecarried for joint vertical movement with the collar. In order to balancethe radial forces acting on the collar the hydraulic rams are dividedinto two groups disposed on diammetrically opposite sides of the collar.

The bearing means between the collar plates and the collar comprises aplurality of rollers spaced circumferentially about the collar at theopposite ends thereof and a pair of roller retainer rings formed on thecollar plates in circumferentially surrounding relation to the rollersfor maintaining vertical alignment between the collar and the collarplates. The peripheral wall of each of the rollers is tapered and rideson a complementarily tapered roller ring for balancing the thrust forcesacting on the rollers.

Many other features, advantages and additional ob jects of the presentinvention will become manifest to those versed in the art upon makingreference to the detailed description which follows and the accompanyingsheets of drawings in which preferred structural embodimentsincorporating the principles of the present invention are shown by wayof illustrative example on y.

Brief description of the drawings FIGURE 1 is a side elevational view ofa rig for boring a casing into the ground constructed in accordance with'the principles of the present invention.

FIGURE 2 is a top plan view of the collar end of the rig takensubstantially along lines IIII of FIGURE 1.

FIGURE 3 is an enlarged side elevational view of the casing end of therig taken along lines IIIIII of FIG- URE 2 with certain structuralmembers broken away to better disclose the relative disposition ofparts.

FIGURE 4 is a fragmentary horizontal sectional view of the rig takenalong lines IVIV of FIGURE 3.

FIGURE 5 is a fragmentary end elevational view taken along lines VV ofFIGURE 1.

FIGURE 6 is a horizontal sectional view taken along lines VI-VI ofFIGURE 5.

FIGURE 7 is an enlarged fragmentary vertical sectional view taken alonglines VIIVII of FIGURE 6.

FIGURE 8 is an enlarged fragmentary vertical sectional view taken alonglines VIII-VIII of FIGURE 5.

FIGURE 9 is an enlarged sectional view of a hydraulic ram mountingbracket and rod clevis taken along lines IXIX of FIGURE 6.

Description of the preferred embodiment In constructing deep caissonsfor the foundations of large structures such as high rise buildings andthe like the rig used in boring the casing into the ground must besubstantial in size because of the great weight and diameter of thecasings the force required to bore the casing and the great depth towhich the casings must be sunk.

Referring to the drawings reference numeral 10 in FIGURE 1 indicatesgenerally a casing boring rig constructed in accordance with theprinciples of the present invention. The rig 10 may be more particularlycharacterized as comprising a frame 11 which includes three framesections indicated respectively at reference numerals 12, 13 and 14. Theframe 11 is adapted to be supported in a horizontal boring position onground level indicated at 16.

Also shown in FIGURE 1 is an exemplary casing 17 mounted in the rig 10and partially bored into the ground indicated at 18. The exemplarycasing 17 is the first of a series of casings to be bored into theground and this first casing is clamped, welded or otherwise fixedlyconnected in end-to-end relation with the next succeeding casing. Thissame procedure is followed as each of the casings is bored into theground until the final casing as dictated by the length of therespective casings and the desired depth of the caisson is bored intothe ground. Since it is assumed the casing 17 is the first of a seriesof casings, a lower edge 19 thereof is provided with cutting teethextending continuously circumferentially therearound. The cutting teethmay be formed integrally with the casing 17 or may be formed on aseparate cutting tool which may be detachably clamped to the lower endof the casing.

The casing 17 is lowered vertically into section 12 by any suitablemeans such as, for example, a crane or similar equipment mounted on theground adjacent the rig 10 or supported on an equipment and crew deck 20of the frame 11. A pair of horizontal table plates indicatedrespectively at reference numerals 21 and 22 are mounted in verticalspaced relation on section 12 and are centrally apertured as at 23 toreceive the casing 17 as it is lowered down into the frame 11.

A plurality of circumferentially spaced casing guide wheels 24 aremounted on the table plates 21 and 22 around apertures 23, 23 forguiding the casing 17 through the apertures as it is being lowered intothe rig. An expansible-contractible casing collar 26 performs thefunction of tightly frictionally gripping the casing 17 after it hasbeen lowered in place and oscillating the casing about its longitudinalaxis while urging it into the ground with great force.

The casing collar 26 is expanded and contracted by means of ahorizontally extending reverse-acting hydraulic cylinder or ram assemblyindicated generally at reference numeral 27. The oscillating motion isprovided by two groups of horizontally extending hydraulic ramsindicated at 28a and 28b which are also of the reverse acting type andwhich are disposed respectively on diametrically opposite sides of thecollar 26. Vertical movement is provided the collar 26 through theutilization of another set of hydraulic rams including rams 29a-29dwhich extend vertically in radially spaced relation to the axis of thecollar 26 and in 90 angularly spaced relation to each other.

Operation of the hydraulic rams 27, 28a-28b and 29a-29d is controlledfrom a hydraulic control console 30 mounted on an operators platform 31in section 13 of the frame 11. The location of the platform 31 affordsthe operator of the rig a vantage point from which to fully observe theoperation of the collar 26 and the vertical headway being made by thecasing 17. The pressurized fluid which services the hydraulic rams issupplied from a series of hydraulic pumps 32 driven by suitable primemovers such as a series of internal combustion engines 33. A speedreducer 34 may be interposed between the engines 33 and the hydraulicpumps 32. The engine-pump assemblies may be mounted on an engine balcony36 located in section 14 of the frame 11 behind the operators platform31.

Each of the frame sections 12-14 comprises a pair of heavy horizontalbeams 37 and 38 and vertical beams 39 and 40 interconnecting thehorizontal beams. A pair of cross-beams 41 and 42 serve as rigidifyingand stabi lization braces for each of the sections 12-14. In operationthe frame 11 may be supported directly on the ground in a horizontalboring position or leveling and supporting leg members may be interposedbetween the frame 11 and the ground as desired or as suggested by thegrade level of the ground.

The collar 26 of the present invention is specially adapted to grip thecasing 17 around the entire periphery thereof and to impart an evenlydistributed radial force on the casing to prevent crimping of the casingto increase the maximum allowable radial and axial forces which can beapplied to the casing and to reduce the radial forces necessary toprovide optimum frictional, forces between the collar 26 and the casingfor joint movement thereof. In addition the collar 26 maintains acylindrical gripping surface as it grips the casing the effect of whichis to assist in bringing into round a casing which is not entirelycylindrical in cross section due to minor defects in manufacture ordeformation through use.

Referring to FIGURES 5 and 6, the collar 26 may be more particularlycharacterized as having a generally cylindrical configuration and ascomprising a plurality of circumferential segments or sections which areindicated for example at reference numerals 43 and which are pivotallyinterconnected to one another on axes which extend parallel to the axisof the collar 26. Each of the segments 43 comprises a plurality ofvertically or axially spaced links as at 44, the links of each of thesegments 43 being circumferentially aligned with respect to one another.The links 44 of circumferentially adjacent segments 43 extend inoverlapping interdigitated relation to one another such that the linksof one segment circumferentially overlap the links of the adjacentsegments and alternate with the links of the adjacent segment in avertical direction.

The overlapping portions of the links 44 of adjacent segments arevertically bored as at 46 for receiving a pivot pin 47 to enable theadjacent link segments 43 to pivot relative to one another as the collar26 is radially expanded and contracted.

Two of the link segments identified at reference numerals 48 and 49 maybe designated as circumferentially spaced end link segmentsinterconnected by a master or spacer link segment 50. The link segmentsother than the end segments 48 and 49 and the master segment 50 may beconveniently referred to as intermediate link segments. In each of thelinks which comprise the master link segment 50 is formed acircumferentially elongated slot 51 arranged concentrically with respectto the collar 26 for receiving a pair of pivot pins 52 and 53 whichextend through circular bores 46 formed in the end links 48 and 49 andhaving substantially the same diameter as the pivot pins 52 and 53 for atelescopic relation therebetween. It is noted that an inner surface 54of each of the links 44 is arcuately shaped and the surfaces 54generally form in the aggregate a cylindrical internal wall of thecollar 26. Within limits of variations in the diameter of the collar 26the internal surfaces defined by the inner walls 54 of the links 44maintain a cylindrical configuration for circumferentially-continuousfrictional gripping action on the outer wall of the casing 17.

Extending radially outwardly from each of the end segments 48 and 49 isa bracket 56 having an end wall 57. The end walls 57 are in verticallyaligned relation with one another and a closure plate 58 is connected infixed assembly by suitable means such as a weld connection or the liketo the end walls 57 of each of the end segments 48 and 49. A series ofbifurcated rod clevises 59 and mounting eye brackets 59a are fixedlysecured to the closure plates 58, 58 and comprise vertically registeredbores 60 for receiving a swivel pin or rod 61.

Referring to FIGURE 7, the ram assembly 27 includes a plurality ofpressurized fluid operated hydraulic rams indicated respectively at27a27c each of which comprises a cylinder 62 and a piston and piston rodassembly 63 slidably carried in the cylinder 62. The cylinders 62 are ofthe reverse-acting type, that is, they are adapted for driving theirrespective pistons in opposite directions. The distal ends of thecylinder 62 and the piston rods 63 are provided with suitablecooperating mounting eye brackets 64 and clevises 64a for pivotallymounting the rams on the swivel pins 61.

After the casing collar 26 has been diametrically contracted tofrictionally grip the casing 17 a vertically downward force is appliedthereto by means of the hydraulic rams 29a29b. The bottom end of each ofthe rams 29a29b is provided with a rod clevis 66 for pivotal connectionthrough a swivel pin 67 with a mounting eye bracket 68 secured in fixedassembly to the lower table plate 22. A cooperating rod eye 69 isprovided at the upper end of each of the rams 29a-29d for connectionthrough a pin 70 to a mounting bracket 71 connected in fixed assembly toan upper horizon or collar plate 72.

The upper collar plate 72 extends horizontally immediately above theupper end of the collar 26 and a companion member which may bedesignated as a lower horizon or collar plate identified at referencenumeral 33 is situated adjacent the lower end of the collar 26. Suitableapertures 74 are formed in the lower collar plate 73 to enable the rams29a29d to extend vertically upwardly therethrough.

The upper and lower collar plates 72 and 73 are connected together infixed assembly by means of a plurality of reaction beams indicatedrespectively at reference numerals 76a-76a'. As shown in FIGURE 6 thereaction beams may be of the I-beam type and in the illustratedembodiment are welded at the opposite ends thereof to the upper andlower collar plates 72 and 73 although it will be appreciated that otherconnecting means may 'be suitably employed.

Thus it is apparent that the collar 26 is confined between the upper andlower collar plates 72 and 73 and is moved vertically by the forceexerted by the rams 29a- 29d as transmitted to the collar 26 through thecollar plates 72 and 73.

The collar plates 72 and 73 are guided for vertical movement only on aplurality of vertically extending slide guides 77a-77d spaced angularlyabout and spaced radially outwardly of the eriphery of the collar 26.The slide guides 77a77a' are connected in fixed assembly at the oppositeends thereof to the upper and lower plates 21 and 22. In the illustratedembodiment the slide guides are cylindrically shaped and extend upwardlythrough apertures 78 formed in the upper and lower collar plates 72 and73. A tubular sleeve bearing 79 surrounds each of the slide guidesbetween the upper and lower collar plates 72 and 73 for free verticalmovement of the collar plates 72 and 73 on the slide guides 77a-77d.

The ram assemblies 28a and 28b which oscillate the collar 26rotationally about its longitudinal axis comprise respectively twogroups of vertically aligned rams indicated at reference numerals 80 and81. One end of each of the rams is mounted on a pivot pin 82 whichextends through vertically registered bores 83 formed in mountingbrackets 84 which are connected to the collar 26 through a mountingplate 86. The opposite end of each of the rams 81 is mounted on a pin 87which extends through mounting brackets 88 connected in fixed assemblyto a corresponding tangentially aligned one of the reaction beams76a-76d.

The rams 80 and 81 of each of the oscillating ram assemblies 28a and 28bare of the dual-acting or reverseacting type whereby the piston membersthereof can be positively driven in opposite directions. Further theassemblies 28a and 28b apply tangential forces to the collar 26 actingalong spaced parallel froce lines and in opposite directions and as thepiston rods of the rams reciprocate there is continually maintained aradially balanced condition upon the collar 26 and the casing 17 duringoscillation of the collar.

The torque applied to the collar 26 is transmitted from the ramassemblies 28a and 28b to the reaction beams 76a-76d, thence to theupper and lower collar plates 72 and 73 and then to the slide guides77a-77d. It will be appreciated that the ram assemblies 28a and 28dmaintain their horizontal disposition at all times, thus simplifying theconnections thereof to the collar 26 and to the opposite force reactionmembers which, in the embodiment, comprise the reaction beams 76a76d.The only movement of the rams 80 and 81 relative to the collar 26 andthe reaction beams 76a-76d other than the reciprocal movement of thepiston rods thereof is a pivotal movement in a horizontal plane. Therams 80 and 81 move vertically jointly with the collar 26, the reactionbeams 76a76d and the upper and lower collar plates 72 and 73 as thecollar 26 is moved vertically. In addition, rams 29a 29d are alwaysmaintained in vertical alignment, thus greatly simplifying theconnections thereof to collar plate 72 and table plate 22.

In order to enable the collar 26 to oscillate freely relative to theupper and lower collar plates 72 and 73 the present inventioncontemplates the provision of bearing means between the collar platesand the adjacent ends of the collar 26.

In the illustrated embodiment a pair of circumferentially spaced rollers89, 89 are mounted on each of the collar links '44 disposed at theaxially opposite ends of the collar 26. Referring to FIGURE 8, each ofthe rollers 89 is journalled on a threaded stud 90 received in acomplementarily threaded bore 91 which extends radially with respect tothe axis of rotation of the collar 26. A sleeve bearing 92 is interposedbetween the roller 89 and the stud 90.

As the collar 26 is oscillated a radial thrust is imposed on the rollers89 due to the circular path in which they travel. In order to balancethis radial thrust peripheral walls 93 of the rollers 89 are tapered toconverge in the direction of the axis of rotation of the collar 26 andride on a pair of wedge-shaped or complementarily tapered roller rings94, 94 connected in fixed assembly to the upper and lower collar plates72 and 73 and arranged concentrically with respect to the circularapertures 23 formed in the upper and lower table plates 21 and 22. Therespective tapers of the rollers 89 and the rings 94 impart anoppositely directed thrust to the rollers 89' to balance the thrustresulting from the rotation of the collar 26, thereby obviatingcomplicated and expensive thrust bearings for journalling the rollers89.

Circumferentially surrounding the roller rings 94, 94

are a pair of roller retainer rings 96, 96 which guide the direction ofmovement of the rollers 89 as the collar 26 is oscillated. The retainerrings 96 are also concentrically disposed with respect to the apertures23 formed in the upper and lower table plates 21 and 22 as well asregistered apertures 97 formed in the upper and lower collar plates 72and 73 as a result of which the collar 26, the upper and lower collarplates 72 and 73 and the upper and lower table plates 21 and 22 aremaintained in vertical alignment.

In the expanded state configuration of the collar 26 the rollers 89 ateither the upper or the lower end of the collar are not in engagementwith their corresponding roller ring 94, depending upon whether thecollar 26 is at rest or is being moved upwardly or downwardly since theoverall distance between the peripheral walls 93 of the rollers 89 atthe opposite ends of the collar 26 is less than the distance between theradially outer portions of the roller rings 94. After the collar 26 isdiametrically contracted, however, all of the rollers 89 are inengagement with their corresponding roller ring 94.

Referring to FIGURE 9, the swivel pins 61 are notched slightly at 61aand crowned as at 61b between the notches 61a at those portions of thepins 61 which extend through the piston rods 63 and the rods themselvesare complementarily curved as at 63a in surrounding relation to thecrowns of the pins. Further, resilient washers as at 65 are disposedbetween the facing surfaces of the clevis 59 and the rod 63.

This arrangement is provided to accommodate any axial movement of thecollar 26 in its expanded state as the bores 83 of the mounting brackets84 which comprise the ram assemblies 28a and 28b.

In order to thoroughly describe the present invention a briefdescription of the operation thereof follows. First of all the operatorof the rig actuates the appropriate control in the control console 30 topressurize the ram assembly 27 to open the end links 48 and 49 and toexpand the diameter of the collar 26. Then a casing 17 is loweredthrough the aperture 23 in the upper table plate 21 and through thecollar 26 until the lower edge thereof abuts either the ground or theupper edge of another casing previously bored into the ground.

If the casing is the first to be bored in a particular hole the leadingedge thereof has the teeth 19 formed thereon. On the other hand if othercasings have been previously bored then the leading or lower edge of thepresent casing is merely securely coupled to the upper end of the nextpreceding casing.

The operator then actuates the appropriate control to pressurize the ramassembly 27 in an opposite direction to contract the collar 26 andfirmly grip the outer wall of the casing. A substantial gripping actionis required in order to provide the necessary frictional force betweenthe collar 26 and the wall of the casing for joint oscillation thereof,and the collar 26 of this invention by avoiding only point contact withthe casing, affords high gripping and friction characteristics withoutcrimping the casing.

When the collar 26 is contracted around the casing 17 it is disposed ina raised position relative to the slide guides 77a-77d. After the collar26 has gripped the casing 17 the operator act-uates the oscillating ramassemblies 28a and 28b as well as the vertical ram assemblies 29a-29d tosimultaneously oscillate the casing 17 about its longitudinal axis andto urge the casing down into the ground.

After the casing has been bored into the ground to a predetermineddepth, the ram assembly 27 is reversely actuated to expand the collar26. The vertical rams 29a and 29d are also reversely actuated to movethe collar 26 again and to its raised position. The collar 26 is thencontracted again to frictionally grip the casing and the vertical rams29a-29b are again pressurized to impose a vertical downward force on thecasing 17. Depending upon the length of the casing it may be necessaryto release and shift the collar 26 on the casing several times to borethe casing substantially its entire length into the ground.

As noted, the collar 26 of this invention not only avoids crimping ordistortion of the casing which might occur under high pressure resultingfrom only point-contact therewith, but also corrects any out-of-round ofthe casing. The application of the vertical and oscillating forces tothe collar 26 through the rams 80 and 81 and 29a-29d are such that thecomponent parts are substantially free of bending moments andcomplicated connecting linkages and relative movements. Even under theheavy strain imposed on the rig the present invention is capable ofserving a long useful life with minimum maintenance. The performancecharacteristics of this invention greatly exceed any other rig of whichI am aware.

Although minor modifications might be suggested by those versed in theart, it should be understood that I wish to embody within the scope ofthe patent warranted hereon all such imodifications as reasonably comewithin the scope of my contribution to the art.

I claim as my invention:

1. In a ground boring and easing rig including a radiallyexpansible-contractible collar for surrounding and securely gripping acasing and means for rotationally oscillating the casing collar andsimultaneously urging thes ame vertically downwardly to bore the easinginto the ground, the improvement wherein said casing collar comprises,

a plurality of link sections arranged in a generally circular pattern incircumferentially successive relation to one another,

the radially innermost surfaces of said link sections being arcuatelyshaped to form together a cylindrical wall for circumferentiallyfrictionally gripping the casing for joint oscillation of said collarand the gripped casing,

means interconnecting circumferentially adjacent ones of said linksections for relative pivotal movement and for relative circumferentialmovement of at least two adjacent ones of said link sections, and

means for moving said relatively circumferentially movable ones of saidlink sections for varying the inner diameter of said collar.

2. The boring and casing rig as defined in claim 1 wherein said adjacentlink sections circumferentially overlap one another and wherein saidinterconnecting means comprises means forming axially aligned aperturesin said link sections and a plurality of pivot pins situatedrespectively in said aligned apertures.

3. The boring and easing rig as defined in claim 2 wherein each of saidlink sections comprises a plurality of axially spaced circumferentiallyaligned links,

all of said link sections having portions circumferentially overlappingadjacent link sections in interdigitated relation.

4. The boring and easing rig defined in claim 1 wherein the radiallyinnermost surfaces of said link portions form together acircumferentially continuous cylindrical wall for completely surroundingthe gripped casing.

'5. The boring and casing rig as defined in claim 4 wherein saidapertures are, formed in said overlapping portions of said links.

6. In a ground boring and casing rig including a radiallyexpansible-contractible collar for surrounding and securely gripping acasing and means for rotationally oscillating the casing collar andsimultaneously urging the same vertically downwardly to bore the casinginto the ground, the improvement wherein said casing collar is generallycylindrically shaped and comprises a pair of circumferentially spacedend segments and a plurality of intermediate segments between said endsegments,

means interconnecting said intermediate segments to the segmentscircumferentially adjacent thereto for pivotal movement on axes parallelto the axis of said collar,

a master spacer segment extending between said end segments, and

means for connecting said master segment to said end segments comprisingcooperating pivot pin and pinreceiving circumferentially elongated slotmeans whereby the master segment serves to maintain the cylindricalconfiguration of the collar as the spacing between the end segments isvaried to vary the diameter of the collar,

each of said collar segments comprising a plurality of axially spacedcircumferentially aligned links,

the links of adjacent segments having portions circumferentiallyoverlapping one another in interdigitated relation.

7. A ground boring and casing rig comprising a'rig frame adapted to besupported in a horizontal boring position,

an expansible and contractible casing collar having a vertical axis ofrotation and adapted to releasably grip a casing for joint movementwith,

means mounting said collar on said frame for relative vertical androtational movement only,

means for selectively expanding and contracting said collar, and

means for selectively moving said collar vertically and rotationallyrelative to said frame,

said collar mounting means comprising,

a plurality of elongated slide guides,

means for mounting said slide guides on said frame for maintaining thesame on spaced vertical axes, and

a pair of horizontal vertically spaced collar plates slidably carriedfor vertical movement on said slide guides and sandwiching said casingcollar therebetween for joint vertical movement there with.

8. The ground boring and casing rig as defined in claim 7 and including,

bearing means interposed between said casing collar and said collarplates for relative rotation therebetween on the axis of rotation ofsaid casing collar.

9. The ground boring and casing rig as defined in claim 8 wherein saidmeans for rotating said collar comprises,

a hydraulic ram having a cylinder end and a piston end operativelyinterconnecting said casing collar and said collar plates for jointvertical movement at both ends thereof with said casing collar and saidcollar plates.

10. The ground boring and casing rig as defined in claim 9 andincluding,

a plurality of vertical reaction beams interconnecting said collarplates in horizontally spaced fixed assembly with one another andwherein said means for rotating said casing collar comprises,

a plurality of horizontally extending hydraulic rams each having acylinder end and a piston end and connected at the ends thereof to oneof said reaction beams and to said casing collar.

11. The ground boring and casing rig as defined in claim 10 wherein atleast one of said hydraulic rams is disposed on one side of said casingcollar and another of said rams is disposed on a diametrically oppositeside to balance the radical forces acting on said casing collar.

12. The ground boring and casing rig as defined in claim 7 wherein saidcollar mounting means further comprises,

vertical hydraulic ram means operatively interconnecting said frame andat least the upper one of said pair of horizontal collar plates forapplying a purely vertical force on said upper collar plate in allvertical positions thereof.

13. The ground boring and casing rig as defined in claim 12 wherein saidvertical hydraulic ram means comprises a plurality of vertical hydraulicrams spaced circumferentially around the periphery of said casing collarto provide a symmetrical balance of the vertical thrust load applied tothe collar plates and to the collar.

14. The ground boring and casing rig as defined in claim 7 andincluding,

bearing means and bearing track means on said casing collar and on saidcollar plates for journalling said collar for rotation relative to saidcollar plates and for maintaining vertical alignment of said collar andsaid collar plates.

15. The ground boring and casing rig as defined in claim 14 wherein saidbearing means comprises a plurality of roller means spacedcircumferentially around said casing collar and wherein said bearingtrack means comprises circumferentially continuous retainer ring meansfor guiding said roller means in a circular path of travel around theaxis of said casing collar.

16. The ground boring and casing rig as defined in claim 15 wherein saidroller means each has an axis of rotation projecting radially from theaxis of said casing collar.

17. The ground boring and casing rig is defined in claim 15 wherein saidroller means are mounted on said casing collar at the vertically spacedends thereof and said retainer ring means comprises a pair of retainerrings formed respectively on said collar plates in circumferentiallysurrounding relation to said roller means.

18. The ground boring and casing rig as defined in claim 17 wherein saidroller means comprises a plurality of rollers each having a taperedperipheral Wall converging in the direction of the axis of said casingcollar and including a pair of wedge-shaped roller rings taperedcomplementarily to the taper of said peripheral walls and mountedrespectively on said collar plates,

the tapered peripheral walls of said rollers being guided by saidretainer rings for rolling movement on said roller rings to balancethrust forces acting on said rollers upon rotation of said collar.

19. Apparatus for boring and sinking a casing in the construction of acaisson comprising,

a frame adapted to be supported in a horizontal position,

at least three spaced vertical slide guides fixedly mounted on saidframe,

a radially expansible-contractible casing collar having a vertical axisof rotation,

a pair of horizontal collar plates above and below the upper and lowerends of said collar having bores for receiving said slide guides forguiding said collar plates in vertical movement,

a plurality of vertical reaction beams connecting said collar plates infixed assembly,

a pair of bearing assemblies interposed between the upper and lower endsof said collar and said collar plates for relative rotation and verticalalignment of said collar and said collar plates,

a plurality of vertical hydraulic rams interconnecting one of saidcollar plates and said frame for raising and lowering said collar, and

a plurality of horizontal hydraulic rams interconnecting said collar andsaid reaction beams for rotationally oscillating said collar.

20. The apparatus as defined in claim 19 wherein said collar comprises aplurality of overlapping interdigitated pivotally interconnected linksextending circumferentially around the collar to grip the casing aroundthe periphery thereof.

21. The apparatus as defined in claim 19 wherein said bearing meanscomprises,

a plurality of rollers mounted on said collar at the upper and lowerends thereof, and

a pair of roller retainer rings mounted respectively on said collarplates in circumferen-tially surrounding relation to said rollers.

22. The apparatus as defined in claim 21 wherein said rollers havehorizontal axes of rotation projecting radially from the axis ofrotation of said collar and wherein each of said rollers furthercomprises a tapered peripheral wall converging in the direction of theaxis of rotation of said collar, and including complementarily taperedroller rings mounted respectively on said collar plates for receivingthe peripheral walls of said rollers in rolling relation.

23. The apparatus as defined in claim 22 wherein said collar comprises,

a plurality of circularly arranged overlapping interdigitated pivotallyinterconnected links including a pair of circumferentially spaced endlinks,

intermediate links between said end links and master linksinterconnecting said end links for providing pivotal and relativelycircumferential movement therebetween for varying the diameter of saidcollar.

24. The apparatus as defined in claim 23 and including means for movingsaid end links relatively circumferentially comprising a hydraulic raminterconnecting said end links and extending transversely to the axis ofrotation of said collar.

25. The apparatus as defined in claim 24 and including,

a pair of brackets operatively connected to said end links,respectively,

said hydraulic ram and said brackets together comprising a rod clevishaving a pair of spaced flanges and a mounting eye bracket interposedbetween the flanges of said clevis, resilient washers between saidmounting eye bracket and said flanges,

means forming aligned bores in said mounting eye bracket, said flangesand said resilient washers, and

a swivel pin extending through said bores.

26. The apparatus as defined in claim 25 and including a convexcrown-shaped peripheral wall formed on that portion of said swivel pinextending through said mounting eye, and

12 1 means forming a complementarily concave wall on said mounting eyesurrounding said crown-shaped portion of said swivel pin. 27. Apparatusfor boring and sinking a casing in the construction of a caissoncomprising a frame adapted to be supported in a horizontal position,

at least three spaced vertical slide guides fixedly mounted on saidframe,

a collar assembly comprising a radially expansiblecontractible casingcollar having a vertical axis of rotation,

a pair of horizontal collar plates above and below the upper and lowerends of said collar,

means for interconnecting said collar plates in fixed assembly and formounting said collar plates for vertical movement on said slide guides,

a pair of bearing assemblies interposed respectively between the upperand lower ends of said collar and said collar plates for relativerotation and vertical alignment thereof,

a plurality of vertical hydraulic rams interconnecting one of saidcollar plates and said frame for raising and lowering said collar, and

a plurality of horizontal hydraulic rams interconnecting said collar andsaid collar plate interconnectingand-mounting means for rotationallyoscillating said collar.

28. A ground boring and casing rig comprising a frame,

casing collar means for releasably gripping a casing,

means mounting said collar means on said frame for vertical androtational oscillating movement relative to said frame,

means mounting on said frame and connected to and effective to oscillatesaid collar means, and

hydraulic ram means mounted on said frame and connected to, andetfective to raise and lower said collar means,

said hydraulic ram including a hydraulic cylinderpiston-piston rodarrangement so disposed with respect to said frame and said collar meansthat the full motive area of the piston is utilized when the collarmeans is being raised and a piston motive area reduced by thecross-sectional area of the piston rod is utilized when the collar meansis being lowered, whereby the power of said hydraulic ram means isgreater in raising than in lowering said collar means.

References Cited UNITED STATES PATENTS 2,576,203 11/1951 Wilson s1 57.1

2,835,969 5/1958 Wheeler 81-66 XR 3,174,562 3/1965 Stow 122 FOREIGNPATENTS 1,442,552 5/1966 France.

1,215,624 5/1966 Germany.

ERNEST R. PURSER, Primary Examiner US. Cl. X.R.

